A population has μ = 75 and a standard deviation of σ = 10.2. What are the mean and standard deviation of the sampling distribution x if a sample of 400 were taken?

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?

Precalculus question, image attached.

The areas of two similar triangles are 72dm2 and 50dm2. the sum of their perimeters is 226dm. what is the perimeter of each of these triangles?